UDC Timing Calculator

Thanks John!

I have replaced the 1.3v you previously provided.
 
Well John if your doing everything for us can you add another sheet so I can just paste my MAPS all in one tab and the then the values populate the correct tab's... :)
 
Huh?? You want to pull your data from UDC and see what it looks like? You can paste everything but duration.
 
Seems everything is protected in my copy I can't paste anything what did i do wrong?
 
Make sure you have the version on post #4, and if you do then your trying to paste in places you shouldn't be.

You might have to create a new sheet if you want to pull data from UDC, then just copy the table and not the labels.

The sheets are protected to keep it from getting corrupt and giving the wrong values.
 
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Protection is a great thing. I can only image the post's you would get with out it..
 
AH64ID, is the 50/50 split BTDC and ATDC to account for the delay between injection and combustion since ideally you want to start the combustion event immediately at or just indistinguishably after TDC? I know I asked about combustion or ignition delay for calculating timing but I am curious as to whether the 50/50 is the approximation for this delay or is there something else at work here. Because the diesel fuel will always have the same amount of ignition delay, hypothetically if the engine is at a constant temperature, then I understand why longer durations down low and shorter ones up high in RPM make sense because you literally have less time to linger in the cylinder before you aren't doing much in the way of optimizing your combustion. Which is where higher pressure comes in to punch that fuel in and shorten the injection event.

The trouble for me is finding that sweet spot because I'm chasing the damn white rabbit of fuel efficiency and not necessarily horsepower. I tow a whole lot and my truck is basically like yours. A 2005 with the NV5600. Fuel efficiency in my opinion requires a lot more care with timing and I just haven't hit the jackpot yet.
 
Ideally yes, but if an injection event takes 30 deg an you get combustion to start at TDC then you won't as much pressure at 12-15 ATDC, where you want it.

So it's a fine line of negative torque (combustion BTDC, which is nearly inevitable) and positive torque.

50:50 is there to increase ignition delay by injecting early, and getting all the fuel in before it's too late for full power potential.

Clear as mud?

One of the reasons I went with larger injectors was to get the same fuel in a shorter duration, to decrease negative torque and increase positive torque.
 
Can someone post a pic of their 2000rpm splits I'd like to see what your running. I'm not entirely sure I understand all the split definitions. For example if I am at 96 at 25-31 load at 2000rpm what does that actually mean?
 
I means that 96% of the fuel is being injected BTDC, and 4% after. The calculator takes actual injection duration (uses rpms, volume, pressure, and duration table) and crank degrees per us to calculate it. So you put 50 in the calculator it will look at the rpms, then the desired quantity of fuel, and the commanded pressure, using those numbers it looks at the duration table to determine how long the pulse needs to be. Let's says it's a 1000us pulse, and you are at 3000 rpms. At 3000 rpms each degree of crank rotation takes 55.6us. So 1000/55.6 is 18.0 which means the injector will be open for 18.0 degrees. Since you have 50 in the calc that means 50% before, a direct split, so the timing table would read 9.0. If you had 100 it would read 18.0, 150 would read 27.0, -100 would read -18.0, -150 would read -27.0, or 96 would read 17.3.

150% means that the injection will start 150% BTDC based on time, so on a 1000us pulse it would start 1500us BTDC which at 55.6 us/deg is 27.0 deg of timing.

Does the make sense?
 
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Clear as mud! LOL So two scenario's for you
1) Cruising at 2000 rpm
2) Pulling a trailer up a hill at 2000rpm
The 96 BTDC would be ok in #1 and very bad in #2
If load were the same.
Only thing different would be pedal position.
 
If the load was the same the pedal position should be the same, but yes you don't want that much timing above the cruise load zone.
 
have you made a you tube video yet of how to use this? buddy of mine is in need of a tutorial, seems like the timer is the way to go.
 
any tips to using this on an 03 / early 04 truck? Angelo is working on his and could use a few ideas if there are any special tricks for the early cr
 
mikmaze said:
any tips to using this on an 03 / early 04 truck? Angelo is working on his and could use a few ideas if there are any special tricks for the early cr
Click to expand...

On my two '03's I run way lower timing than on the 04.5 and up. Here is a pic of the timing splits on my wife's truck. It has stock injectors, an S363, dual CP3's, and 35" tires.

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Yup, the early CRs don't like as much timing at low/mid rpms, and a much lower ramp rate at upper rpms than the late CRs.
 
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